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Security Parts carries parts for the Von Duprin 22, 33A/35A, and 55 Series exit devices. The 22 Series is the economy wide stile device for medium-to-low traffic with a 3-13/16 inch minimum stile. The 33A/35A is the narrow stile pushpad device with a fluid dampener, deadlocking latch, and concealed VR configurations for stiles as narrow as 2-1/8 inches. The 55 Series is the traditional crossbar device for aluminum storefront doors with stiles as narrow as 1-3/4 inches. Key shared parts: the dogging shaft and adapter work across 22, 33A, 98, and 99 Series. The 33A/35A ALK alarm kit is compatible with 22, 33A, 35A, 98, and 99 Series. The 55 Series uses dedicated narrow stile trim that is not interchangeable with any other Von Duprin series.
Von Duprin invented the first self-releasing fire exit device over a century ago. The 22, 33A/35A, and 55 Series represent three distinct product lines that together cover the majority of commercial egress doors installed in North America from the 1970s through today. When one of these devices needs a replacement part, the most critical first step is confirming which series is installed. Parts from the 33A/35A will not work on the 22. Parts from the 55 will not work on either. Trim from the 98/99 will not fit the 55. Getting the series wrong generates a return.
Browse the complete Von Duprin parts catalog at SecurityParts.com for 22, 33A/35A, 55, and all other Von Duprin series with interactive diagrams. For the full exit device catalog including Falcon exit devices alongside Von Duprin, browse the commercial exit device parts catalog.
Three Series, Three Applications: How to Choose and Why It Matters for Parts
Von Duprin 22 Series
Modern touch bar styling for medium to low traffic openings. 3-13/16 inch minimum stile. Rim (22) and surface VR (2227) only. No concealed VR version. Compatible with 22-ALK alarm kit and limited trim options. Covers 161 door prep. UL listed for panic and fire (22-F). Made in USA. Best for clinic/healthcare back doors, multi-family entries, retail secondary exits.
Von Duprin 33A/35A Series
Deadlocking latch, fluid dampener, pushpad design. 1-3/4 inch minimum stile. Rim (33A/35A), surface VR (3327A/3527A), concealed VR (3347A/3547A, stile to 3-1/2 inch), and narrow concealed VR (3348A/3548A, stile to 2-1/8 inch). Full electrified option range. 33A has grooved case; 35A has smooth case. Both mechanically identical. Not compatible with older 33/35 pre-2002 parts.
Von Duprin 55 Series
Classic crossbar design for aluminum framed glass storefront and narrow stile doors. 1-3/4 inch minimum stile. Rim (55) and concealed VR (5547). Handed device: specify LHR or RHR when ordering. Uses dedicated 55 Series trim: 550DT, 555NL, 379L. Standard 98/99 or 33A trim does not fit. Production since at least the 1970s. Historic aesthetic, maximum activation zone, visual transparency due to no bulky mechanism case.
Von Duprin 22 Series Parts
The 22 Series is the value-line option in the Von Duprin exit device catalog. It is not a light-duty device: it carries the same ANSI A156.3 Grade 1 certification as the 33A/35A and 98/99 Series and is UL listed for both panic and fire hardware. What distinguishes it from the 33A/35A is the absence of a fluid dampener and deadlocking latch, a narrower trim compatibility range, and no concealed VR configuration. For doors where these features are not required, the 22 Series provides genuine Von Duprin Grade 1 quality at a more economical price point.
22 Series Center Case
The center case is the core mechanism housing that contains the latch bolt and push bar actuating mechanism. The 22 rim device center case and the 2227 surface vertical rod center case are different parts and not interchangeable. The 2227 (SVR version) has a separate center case because it must accommodate the rod actuating mechanism in addition to the latch bolt. When ordering a replacement center case, always confirm whether the installed device is a 22 rim (single latch point) or 2227 SVR (two-point latching with top and bottom rods).
22 Series Dogging Cover Plates
The dogging cover plate covers the dogging assembly on the hinge side of the exit device. It is a frequently lost or damaged component. On 3-foot devices, the cover plate part number is 968595 (10-3/4 inches long). On 4-foot devices, the cover plate is 968596 (16-3/4 inches long). These cover plates are device-length specific. Installing a 3-foot cover plate on a 4-foot device leaves the dogging assembly exposed and vulnerable to damage and debris accumulation.
22 Series End Cap and 2227 Rod Guide Assembly
The end cap covers the hinge-side end of the mechanism channel. The 22 Series uses the 050014 impact-resistant end cap kit (shared with 33A/35A and 98/99 Series) which replaces all previous end cap versions. This cross-series compatibility is one of the few shared parts between the 22 and 33A/35A families.
The 2227 rod guide assembly 112063 replaces the older style SVR rod guide that used a plastic cap and springs. The new rod guide adds strength and rigidity to the top and bottom rods on the surface VR version. If the rods on a 2227 installation show visible flex or misalignment during operation, the rod guide assembly is the correct replacement.
22 Series Trim and Cylinder Compatibility
The 22 Series uses the 230L lever trim (works on both 22 rim and 2227 SVR) and the 210L knob trim. The trim-to-device interface on the 22 Series uses a tailpiece guide (part 22-ALK, 33A-ALK, 35A-ALK, 98-ALK, and 99-ALK are all the same tailpiece guide) that guides the rim cylinder tailpiece into the back of the exit device. This part is shared between the 22, 33A, 98, and 99 Series.
Von Duprin 33A/35A Series Parts
The 33A/35A Series is Von Duprin's highest-performing push pad exit device for narrow stile applications. The fluid dampener, deadlocking latch, and full concealed VR configuration range set it apart from both the 22 Series and the 55 Series for any application requiring high performance on a narrow stile door. Understanding the parts requires knowing which configuration is installed, because center cases, cover plates, and rod assemblies differ across rim, surface VR, and concealed VR versions.
33A vs 35A: The Case Style Distinction
The 33A has a grooved (ribbed) mechanism case exterior. The 35A has a smooth mechanism case exterior. Both are mechanically and dimensionally identical in every other respect. All internal parts, including the center case assembly, dogging shaft, end cap, latch bolt, and fluid dampener, are the same between 33A and 35A. When ordering parts for a 33A/35A device, the case style (grooved vs smooth) does not affect internal part numbers. It only affects the external center case cover, which is a cosmetic and protective component that is series-specific but not interchangeable between grooved and smooth styles.
Fluid Dampener: The Noise-Reduction Component
Every 33A/35A exit device is equipped with a fluid dampener that decelerates the push pad on its return stroke after being pressed. This is the feature that makes the 33A/35A appropriate for quiet-operation environments: healthcare corridors, educational facilities, and any space where the metal-on-metal snap-back of an un-dampened push pad would be a noise disturbance.
The fluid dampener is part of the mechanism case assembly. It cannot be replaced as a standalone field component: the dampener is integrated into the center case during manufacturing. If the dampener fails (indicated by loud snap-back noise on push pad return that was not previously present), the center case assembly replacement is the correct service action.
33A/35A Concealed Vertical Rod Configurations
The 33A/35A Series offers two concealed vertical rod configurations for different stile width situations.
3347A/3547A (concealed VR, 3-1/2 inch minimum stile): Used on hollow metal single and double doors where the stile is 3-1/2 inches or wider. The concealed rods run inside the door stile with no visible rod hardware on the door face. The top latch (part 050494) is used on both 33A, 35A, 98, and 99 concealed VR devices. This cross-series compatibility on the concealed top latch is one of the few cases where 33A/35A and 98/99 parts overlap on CVR configurations.
3348A/3548A (narrow concealed VR, 2-1/8 inch minimum stile): Used on hollow metal doors with stiles as narrow as 2-1/8 inches. This is the narrowest concealed VR configuration in the Von Duprin line and is specified on doors that cannot accommodate the 3347A minimum stile. Fire-rated versions (3348A-F and 3548A-F) support 8-foot by 10-foot door pairs at UL fire listing.
| Configuration | Model | Min Stile | Latching | Notes |
|---|---|---|---|---|
| Rim | 33A / 35A | 1-3/4 inch | Single point rim latch | Non-handed except with SS option |
| Surface VR | 3327A / 3527A | 3-5/8 inch | Two-point: top latch + bottom rod | Non-handed except with SS option |
| Concealed VR (wide) | 3347A / 3547A | 3-1/2 inch | Two-point concealed rods in stile | 5/8 inch throw. Non-handed except SS |
| Concealed VR (narrow) | 3348A / 3548A | 2-1/8 inch | Two-point concealed rods in stile | 5/8 inch top, 1-1/2 inch bottom throw. Non-handed except SS |
| Concealed VR cable | 49A | Less specific | Two-point concealed vertical cable | Available less bottom latch (LBL) |
33A/35A and 22 Series Shared Dogging Shaft
The dogging shaft and dogging adapter that have been in production since 1998 are shared across the Von Duprin 22, 33, 33A, 98, and 99 Series devices. This is confirmed by the official Von Duprin parts catalog. The dogging shaft is the current standard replacement for any of these series when dogging function fails. The hex key dog conversion kit (parts 050114 and 050117) converts 33A and 99 Series hex key dogging to cylinder dogging, allowing a standard mortise cylinder to control dogging without carrying a hex key. The conversion kit does not include the cylinder.
33A/35A Alarm Kit (ALK)
The ALK alarm kit converts a 22, 33A, 35A, 98, or 99 Series exit device to an alarmed device. When the push bar is pressed, a 100dB battery-powered alarm sounds. The kit is powered by a standard 9-volt battery and controlled by a mortise cylinder (not included). The kit includes the EMERGENCY EXIT ONLY. ALARM WILL SOUND decal. An ALK power supply is available for hardwired operation of one or two alarm kits from a single 12V or 24V power source. Browse the exit alarm parts catalog at SecurityParts.com for ALK kits and Detex and Von Duprin Guard-X alarm components.
Von Duprin 55 Series Parts: The Crossbar Legacy Line
The Von Duprin 55 Series has been in production since at least the 1970s. It is the traditional crossbar exit device: instead of a push pad, it uses a suspended metal crossbar that spans nearly the full door width and activates the latch mechanism when any part of the bar is pressed. This design predates the push pad era and remains in production because it serves two applications that the pushpad cannot match: it is the only Grade 1 Von Duprin device for storefront aluminum doors with stiles at the absolute minimum of 1-3/4 inches, and it is the correct retrofit device for historic and mid-century buildings where maintaining the crossbar aesthetic is an architectural requirement.
55 Series Center Case (Part 050183)
The 55 Series center case (part 050183) is the core replacement housing for the 55 rim device. It includes all internal workings and the latch bolt. The center case geometry on the 55 Series is completely different from the 22, 33A, or 98/99 Series. Center cases are not cross-compatible. When ordering a replacement 55 Series center case, confirm the device is a 55 rim (single latch point) rather than the 5547 concealed VR, as these are different assemblies.
55 Series Lever Arm and Hinge Case Axle
The 55 Series uses a lever arm mechanism that connects the crossbar to the center case and activates the latch when the crossbar is pressed. The lever arms are handed: right hand (050355) and left hand (050356). Always confirm the device handing before ordering a lever arm.
The center case axle (090050) is used on the 55 rim device. The hinge case axle (090051) is used on the inactive housing (hinge side) and on all other 55 configurations including the 5547 CVR device. The arm bushing (050333) takes up the mechanical slack between the lever arms and the housing; it is a wear component that should be checked when lever arm movement feels loose or imprecise.
55 Series Trim: Dedicated and Non-Interchangeable
The 55 Series uses narrow stile-specific outside trim that is not compatible with any other Von Duprin series. The three standard trim options are 550DT (dummy pull, non-functional outside handle), 555NL (night latch with outside cylinder that locks and unlocks the push bar), and 379L (outside lever trim). Standard Von Duprin 360L, 230L, or 99/98 Series trim will not fit the 55 Series because the mechanism case geometry is different.
When a 55 Series installation needs outside trim replacement, always order from the 55-specific trim range. When a building has a mix of 55 Series and 98/99 or 33A devices, the trim from one series cannot be used on the other even if the finish matches.
5547 Concealed Vertical Rod: The 55 Series Double-Door Solution
The 5547 is the concealed vertical rod version of the 55 Series, used on double-door aluminum storefront configurations where both doors need the crossbar aesthetic with concealed rod latching. The 5547 blind fastener kit (900539) connects the rod control housing to the rods and is specific to the 5547 CVR only. The 5547 uses the hinge case axle (090051) as does all 55 Series hardware except the 55 rim center case.
Parts Cross-Compatibility: What Works Across Series and What Does Not
The most expensive parts ordering mistakes on Von Duprin exit devices happen at the series boundary. Some parts cross series; most do not.
| Part | 22 | 33A/35A | 55 | 98/99 |
|---|---|---|---|---|
| Current dogging shaft (post-1998) | Yes | Yes | No | Yes |
| Impact-resistant end cap kit 050014 | Yes | Yes | No | Yes |
| Tailpiece guide (ALK suffix) | Yes | Yes | No | Yes |
| ALK alarm kit | Yes | Yes | No | Yes |
| Concealed top latch 050494 | No | Yes (CVR) | No | Yes (CVR) |
| 230L lever trim | Yes | No | No | No |
| Shear pin 050156 | Yes (230L/360L/992L) | Yes (same trims) | No | Yes (same trims) |
| Center case assembly | 22 only | 33A/35A only | 55 only | 98/99 only |
| Latch bolt | 22 only | 33A/35A only | 55 only | 98/99 only |
How to Identify the Correct Series Before Ordering
The series identification that prevents a wrong-part return takes under 30 seconds on any Von Duprin installation.
Is there a push pad or a crossbar? A crossbar spanning most of the door width = 55 Series. A push pad (compact rectangular bar) = 22, 33A, 35A, 98, or 99 Series. Go to the next check.
Is the door stile wide (4 inches or more) or narrow (under 4 inches)? Wide stile hollow metal doors most often have 98/99 or 22 Series. Narrow stile aluminum storefront doors most often have 33A/35A or 55 Series. The device label on the mechanism case confirms the exact series.
Check the mechanism case label. The series number is on a label on the center case. This is the definitive identification. On the 33A, the case exterior has visible ribs (grooved). On the 35A, the case is smooth. Both are current generation if the center case cover is one piece. Older 33/35 Series (pre-2002) have a two-piece center case cover.
Browse the Von Duprin parts catalog at SecurityParts.com with interactive diagrams for all series. For Von Duprin electric strike parts compatible with 22 and 33A/35A rim exit devices, browse the electric strikes catalog. For Von Duprin Guard-X exit alarm parts, browse the exit alarms catalog. For the full Falcon exit device catalog as an alternative brand, browse the Falcon hardware catalog. Pre-order support is available at 845-935-0301 or through the contact page.
Why Choose Security Parts for Von Duprin 22, 33A/35A and 55 Series Parts
Series cross-compatibility table, 33/35A vs 33/35 generation warning, shear pin documentation, fluid dampener failure diagnosis, and same-day shipping on stocked parts.
Cross-Compatibility Table
We document which parts work across 22, 33A/35A, 55, and 98/99 Series. The dogging shaft and end cap are cross-series. Center cases and latch bolts are not. This table eliminates the most common wrong-series order.
Generation Warning
We document that 33A/35A parts are not compatible with pre-2002 33/35 Series devices and how to identify the generation from the center case cover. No other parts supplier explains this before the order is placed.
Shear Pin and Dampener
We document the shear pin as the first-check component after any forced entry on a 230L or 360L lever trim, and the fluid dampener as the cause of sudden push pad snap-back noise on 33A/35A devices.
Same-Day Shipping
Most 22, 33A/35A, and 55 Series parts ship same day from US warehouses. Call 845-935-0301 or use the contact page for series identification support.
What Makes Security Parts Different for These Von Duprin Parts
- We document the parts cross-compatibility table showing which parts work across 22, 33A/35A, and 98/99 Series (dogging shaft, end cap, tailpiece guide, ALK) versus which are series-exclusive (center case, latch bolt, trim). No parts supplier makes this available at the ordering stage.
- We document the 33/35 vs 33A/35A generation boundary with the one-piece vs two-piece cover identification method. The 2002 redesign created a complete parts break that generates returns on any order where the generation is not confirmed first.
- We document the shear pin (050156) as the sacrificial component in 230L, 360L, 992L, 994L, and 996L lever trims. Most technicians who encounter a loose lever after a forced entry event replace the trim assembly when only the shear pin has failed.
- We document the 55 Series sagging crossbar as an installation torque issue on the wedge screws, not a parts failure. This eliminates unnecessary service calls and parts orders on new 55 installations.
- We carry a wide range of parts, including Von Duprin, electric strike, exit alarm, LCN door closer, Schlage cylindrical lock, and mortise lock parts, providing comprehensive building hardware service in a single order.
- Free shipping on orders over $450. Same-day shipping from US warehouses on stocked parts. 30-plus years of commercial door hardware experience.
Related Parts and Products at SecurityParts.com
Von Duprin 22, 33A/35A, and 55 Series exit devices typically appear on egress doors alongside electric strikes for controlled entry and LCN door closers for self-closing operation on fire-rated assemblies.
For Von Duprin 5100, 6100, 6200, and 6300 electric strike parts compatible with 22, 33A/35A, and 55 Series rim devices, browse the electric strikes catalog. For Von Duprin Guard-X and Detex ECL and EAX exit alarm parts, browse the exit alarms catalog. For LCN door closer parts on fire-rated egress doors in the same building, browse the door closers catalog. For Schlage ND and ALX Series cylindrical lock parts on interior doors in the same facility, browse the cylindrical locks catalog. For Falcon 19, 24, and 25 Series exit device parts as an alternative brand on newer or renovation egress doors in the same building, browse the Falcon hardware catalog.
Browse the complete all products and parts catalog to source Von Duprin, Schlage, LCN, Falcon, and Detex hardware across the complete facility in a single session.
Frequently Asked Questions About Von Duprin
22, 33A/35A and 55 Series Exit Device Parts
What is the difference between the Von Duprin 22 and 33A/35A Series exit devices?
The 22 Series is the economy option with modern touch bar styling, a 3-13/16 inch minimum stile, and rim and surface VR configurations only. The 33A/35A is the higher-performance narrow stile device with a deadlocking latch, fluid dampener for quiet operation, stiles as narrow as 1-3/4 inch, and a full configuration range including rim, surface VR, and concealed VR. The 33A has a grooved case; the 35A has a smooth case. Both are mechanically identical.
What is the Von Duprin 55 Series and when should it be specified instead of the 33A/35A?
The 55 Series is a traditional crossbar exit device for aluminum storefront and glass doors with stiles as narrow as 1-3/4 inch. It should be specified over the 33A/35A when retrofitting doors with existing crossbar hardware, when maintaining a historic or retro architectural aesthetic is required, or when maximum push bar activation area is needed. The 55 Series uses dedicated narrow stile trim (550DT, 555NL, 379L) that is not interchangeable with any other Von Duprin series trim.
What is the dogging shaft on Von Duprin exit devices and when does it need replacement?
The dogging shaft locks the push bar in the depressed position for free-swing operation during business hours. The current shaft design for 22, 33, 33A, 98, and 99 Series has been in production since 1998. Replace when it is difficult to turn, no longer holds the push bar dogged, or is physically bent. A hex key to cylinder dogging conversion kit (050114 and 050117) is also available for 33A and 99 Series to allow mortise cylinder control.
What is the 33A/35A fluid dampener and why does it matter?
The fluid dampener decelerates the push pad on its return stroke to reduce the snap-back noise associated with standard exit devices. It is integrated into the mechanism case and cannot be replaced as a standalone component. If a 33A/35A device begins producing loud push pad snap-back noise that was not previously present, the center case assembly replacement restores quiet operation. Lubrication and spring adjustment do not resolve a failed dampener.
Will Von Duprin 33A/35A Series parts work on older 33/35 Series devices?
No. The 33A/35A redesign in 2002 created a parts break with the older 33/35 Series. Most current parts are not compatible with pre-2002 devices. Identify the generation by the center case cover: one-piece cover = current 33A/35A. Two-piece cover = older 33/35. Contact SecurityParts.com for compatible parts identification on older devices before ordering.
What is the Von Duprin ALK alarm kit and which series does it work with?
The ALK alarm kit adds a 100dB battery-powered alarm to an existing exit device that sounds when the push bar is pressed. It is compatible with Von Duprin 22, 33A, 35A, 98, and 99 Series devices. It runs on a 9-volt battery and is controlled by a mortise cylinder (not included). The ALK does not work on the 55 Series. A hardwired ALK power supply is available for connecting one or two alarm kits to a 12V or 24V power source.